1) A kiwi slice that explodes on the platform above you (assuming standard 3-block height between platforms) will not hurt you. At least, it didn't hurt me. I am not about to try again to make sure.
2) An umbrella took me to level 75. The items appeared as normal. The only time they don't is when you play PD72. That is so weird.
3) If a pear spits his Baddybomb into a portal from far enough away (esp. on 84), it will land directly in front of the portal and you will not be able to kick it back through to him. Be wary.
4) If your video card supports it, you can press Ctrl+Alt+Down to flip your monitor display upside-down, thus counteracting the effects of the shades in PD97. You're welcome.

(Unfortunately, MY video card doesn't let me do this.

)